Electric switch, connector, and the like



March 31, 1942. R. BoRzA 42,278,957'

ELECTRIC SWITCH, CONNECTOR, AND THE LIKE 2 Sheets-Sheet Al Filed Marchl5, 1941 NVENTOR.

March 31, 1942'. R, BORZA 2,278,057

ELECTRIC SWITCH, .CONNECTOR AND THE'v LIKE Filed Marh l5, 1941 2Sheets-Sheet 2 g Ill/[lll] l v fr" mvENToR. RAF/#15! M24 Arme/VirPatented-Mar. 194.2.

UNITI-:D` STATES PATENT cil-Fica ELECTRIC SWITCH, CONNECTOR, AND THE'`Raphael Bom, Yonkers, N. Y. Application March 15, 1941, SerialNo.383,282

(Cl. 20o-162) 5 Claims.

This invention relates to electric switches, and aims to provideimprovements whereby a practically perfect electric contact is hadbetween the movable and the stationary contacts.

-The above and other objects will become ap-` parent in the descriptionbelow, reference being had to the accompanying drawingswherein a numberof different types of electric switches or contactors are illustrated.It is not intended to limit the invention to the specific details ofconstruction shown, nor to the particular types of switches orcontactors illustrated, as it may equally well be applied to other typesor forms.

Referring briefly to the drawings,

Figure l is a plan view of a knife switch embodying the invention.

Figure 2 is a side elevational view of the same.

Figure 3 is a cross-sectional view taken on the line 3 8 of Figure 2.

Figure 4.is a cross-sectional view taken on the line 4 4 of Figure 2.

Figure 5 is a cross-sectional view taken on the line 5 5-of Figure 3.

Figure 6 is a side elevational viewvof a contact plug socket embodyingthe same invention.

Figure 7 is a cross-sectional view taken on the line 1 1 of Figure 6.

Figure 8 is a cross-sectional view taken on the line 8 8 of Figure 7. i

Figure 9 is a cross-sectional view taken on the line 9 9 of Figure 7.

Figure l0 is a plan view,'partly in section and with part of the coverremoved, of a so-called electric iron plug socketl embodying the sameinvention.

Figure 11 is a cross-sectional view taken on the line Il II of Figurel0.

Figure 12 is a cross-sectional view taken on the line I2 I2 of Figure1l.

' Referring in detail to the drawings, the numeral I0 indicates the baseof a knife switch, the

pedestal II, secured thereon, having the throw arm or blade I2 pivotedthereto. The Contact or pole I3 is similarly secured to the base. Forthe sake of simplicity, the wire terminals are not shown.

The pole I3 comprises a unitary'member having a pair of opposed rigidupright arms I 4 and I5 extending therefrom. the space between thesearms having a oor I6. The mutually opposed or inner walls I1 and I8 ofthese arms are very slightly inclined in a downward direction withrespect t o each other, so that the said space between the arms isslightly wedge-shaped. In the illustration, the wall I1 is shownperpendicular to the base I8 and the wall I8 at a slight a'ngle to theperpendicular.

An L-,shape'd block I8 is slidably mounted against the wall I8, and iskeyed against lateral movement by a pin 20 registering loosely in0pposed cylindrical grooves 2| and 22, the former in the wall. I8 of thearm I5, and the latter in the wall of the block I 9. The opposed wallsof the block I! are also very slightly tapered with respect to eachother, but in the opposite direction to that of the arm walls I1 and I8.A coiled spring 23, registering 'in a' recess in the oor I6, normallyurges the block I9 upward. An angular slot 24 is cut acrossthe top of.the block I9 'and a tongue 25, screwed to the top of the arm I5, isadapted to register in the slot to serve as an upper limit stop, toprevent the block from leavingv the space between the arms.

It is apparent that, as the blade I2 is forced into the .pole I3, itengages the block I9 and carries the same with it. In so doing, theadjacent surface of the block is forced into closer and tighter contactwith the blade, owing to the wedge-shape of the block and theinclination of the arm wall I8. Upon extraction of the blade, the spring23 restores the block to an upper position, as is obvious.

The pedestal II is provided with similar partsv and is in generallysimilarly constructed. the

externally visible parts thereof being indicated, in Figures 1 and 2,with identical numbers followed by the letter al Of course, any othersuitable guide means, to prevent lateral movement of the block I 9, maybe provided instead of the loose key and slot arrangement shown.

Itis apparent from the above that a switch has been provided whereby,when in closed position, practically no loss of power is entailed, owingto the snugness of the contacts. As a result, heavily loaded switchesmay be built substantially smaller in size than is at present necessary.

In the application of the principle of the invention to a simple plugsocket of the common two-prong type shown, the members 26 are rigidwithin the housing 2'I and are provided with suit-- able contactterminals, not shown, for the leads. That portion of each member 26,shown at 26a,

which registers in the recesses in the housing, is f tubular andrectangular in cross-section, with the wall 2Gb tapering toward theopposite wall as shown. Slidably mounted within the tube 26a, betweenopposed walls thereof, is a deformed resilient Wedge-like finger 28having a tongue 29 extending inward toward the axis of the housing. Ascrew 30 is insertable into the housing in the axis thereof, and carriesa loose insulated Washer 3| urged `outward by a spring 32. The tongues23 of the wedges 23 are both in touch with the washer 3|, and are urgedby the spring 32 acting against the washer, into their tubular homeswithin the sections 28a. When the prongs 33 of a plug, not shown, 'areinserted into the socket 421, and their tips reach the tongues 23,further the two hollow tubes or sleeves 35 which are adapted to receivethe cylindrical prongs, not shown, of the plug. In each sleeve 35 aslidable contact member 36 is mounted, and its rear is deformed into aZ-shaped extension 31. shown, the sleeves 35 taper inwards, and as theprong is inserted into the sleeve from the front,

its tip carries the member 36 inward by engagement with extension 31,thus causing a wedging action which tightens the electrical contact. Acoiled spring 39 is placed between the inner,

y reduced and closed end of the sleeve, and the free end thereof liesagainst the extension 31 of the member 36. vIndents 38 in the opposedside walls of the sleeve, lying in the path of the extension 31, act aslimit stops to prevent passage of the members 36 out through the mouthof the tube 35. The springs 39, obviously, urge the `mem bers 36 outwardagain, to the position shown, on extraction of the prongs of the plug.

It is apparent from the above that a practical meanshas been providedfor greatly enhancing the efficiency of electrical contact in suchdevices as switches and contact plugs. modifications in form andstructure maybe made without departing from the spirit and scope of theinvention.

I claim:

' 1. In combination, a male contact membergand a female contact 4memberadapted to receive and make electrical contact with said member, saidfemale member having a metallic lined recess therein and a metallicmember slidable in said recess, said recess tapering inward, said slid.

able-member having an extension thereon adapt-'- ed to belengaged bysaid male member upon insertion of the latter into the recess and to becarried rearward thereby toward the tapering end of the recess, saidmovement of said male and slidable members causing said slidable memberto wedge said male member tightly in said Y recess, said femalev memberand said slidable member having opposed complementary longitudinal'grooves therein, a pin mounted partly in ea'ch of said grooves, andresilient means for restoring said slidable member to its originalforward position in said recess upon extraction of said male member fromsaid recess.

2. In combination, a male contact member and a female contact memberadapted to receive and make electrical contact with said member, saidfemale member having a metallic lined recess therein and an L-shapedmetallic block slidable in said recess, said recess tapering in-Obviously,

^ ward, said one arm of said block forming an exing 34 is of standardconstruction and contains tensionthereon adapted to be engaged by saidmale member upon insertion of the latter into the recess and to becarried rearward thereby toward the tapering end of the recess, saidmovement of said male and slidable members causing said slidable memberto wedge said male member v tightly in said recess, said female memberand said block having opposed/complementary longitudinal groovestherein, a pin mounted partly in each of said grooves, and resilient-means for restoring said slidable member to its original forwardposition in said recess upony extraction of said male member fromsaidrecess, and a limit stop to limit the forward movement of said slidablemember.

3. In combination, a' male contact member and a female contact memberadapted to receive and make electrical contact with said member, saidfemale member having, a metallic lined recess therein and an L-shapedmetallic member slidable in said recess, said recess tapering inward andthereby constituting a wedge-shaped recess,

, member to wedge said male member tightly in said recess, resilientmeans for restoring said slidable member to its original forwardposition in said recess upon extraction of said male member from saidrecess, and guide means limiting said slidable member to longitudinalmovement and constraining the same -against lateral movement.

4. An electrical socket comprising a hollow housing having spaced plugopenings through one wall thereof, a pair ofspaced contact membersmounted in the housing, the opposed wallsof said members tapering in arearward direction from said openings, the forward ends of said membershaving rearwardly tapering tubes rectangular in cross-sectionformedthereon, said tubes being open at both ends and having their forwardends lyingadjacent said plug openings, members slidably mounted in saidtubes and having extensions on the rearward ends thereof, saidextensions projecting toward each other out of the rearends of saidtubes, a stud secured in said housing between said extensions and havingf a washer-like member slidable thereon, and resilient means normallyurging said last-named member in a forward direction against saidextensions to normally urge said slidable members forward in theirrespective tubes.

5. An electrical socket comprising a housing having an opening in theforward end extending rearward thereof, a tube registering in saidopening and tapering rearward, a contact member longitudinally slidablein said tube and having a-substantially 4right-angled extension on therearward end thereof, a coiled spring mounted between the rear end ofsaid tube and said extension, said sleeve having intermediate its lengthprojections on the opposed inner walls thereof positioned forward ofsaid extension and serving as limit stops to the forward movement ofsaid member, said spring urging said member o forward and simultaneouslyurging the same

